Low-velocity impact performance of 3D-printed PLA/Epoxy/Glass fibers of composite structures and latches

Abstract

The integration of 3D printing into the synthesis process of polymeric composite structures can offer significant advantages in producing geometrically complex parts. Moreover, engineering components may be subjected to impact loads that can adversely affect their performance and, in some cases, lead to failure. Traditionally, fiber-reinforced composite structures have demonstrated improved responses to applied mechanical loads. In this study, we designed multi-material polymer-based composite structures to enhance structural responses to impact loads. Employing fused filament fabrication (FFF) and solution casting methods, we manufactured PLA lattice infilled with epoxy/Milled Glass Fibers (MGFs) of composite structures with varied MGFs content ranging from 0 to 7.5 vol%. The research provides a comprehensive analysis of the impact behavior of glass-fiber reinforced composite structures, specifically focusing on PLA lattice frames filled with epoxy resin and varying levels of MGFs. Through low-velocity impact tests, the study assesses key parameters such as peak force, peak absorbed energy, residual velocity, and displacement, providing insights into the materials' response to impact loading conditions. The findings highlight the effect of MGF reinforcement on enhancing the impact toughness and resistance to crack propagation, with higher MGF content leading to improved mechanical properties. The microstructural analysis demonstrates the morphology and interface bonding of the composite materials, elucidating the mechanisms. Finally, latches were designed, and their impact behavior was tested to examine the usability of the composite structure in real-life components. The results suggest that the incorporation of MGFs in 3D-printed composite latches significantly enhances their impact resistance, with potential implications for various engineering applications.